The gunmen pulled up outside the offices shortly after 7 p.m. and fired at three people, a police spokesman said, leaving two dead and a third hospitalized with serious injuries.

The spokesman, who was not authorized to give his name, said it was premature to say whether the attack, in the suburb of Neo Iraklio, had been political. The police said that 15 9-millimeter shell casings had been recovered, contradicting earlier reports in the Greek news media that Kalashnikov assault rifles were used in the attack.

In a statement posted on its website, Golden Dawn said the dead were “two young kids” in their mid-20s who were shot at close range. The statement suggested that the attack had a political motive. “Golden Dawn had asked for police protection for its offices, as it had received threats, but the treacherous coalition of Samaras refused,” the statement said, referring to Prime Minister Antonis Samaras.

The party’s statement did not identify the victims by name, noting only that it regarded them as “members of our family,” but a Golden Dawn member of Parliament, Ilias Panagiotaros, told Greek radio that the two had been party members.